1. Field of the Invention
The present invention relates generally to the field of dispensing a vaporized material into the ambient and, more particularly, to air freshener devices for emitting a vaporized air freshening material into the ambient.
2. Description of the Prior Art
Prior art air freshener devices are of many different types. These may be classified into two broad categories, namely, those which rely upon natural convection of room air to evaporate and diffuse air freshening material throughout a room, and those which rely upon forced air circulation (for example, by means of a motor-driven fan) to enhance the evaporative and distributive processes. Air freshener devices which fall within each of these two categories may dispense evaporated material from any one of a number of different types of sources. These include liquid-containing reservoirs, paste or gel containers and impregnated, porous media.
Some air freshener devices of the type which employs a motor-driven fan to evaporate and dispense material from an impregnated medium incorporate a cartridge-type medium which has a dry cell battery nested concentrically within the cartridge. These devices suffer the disadvantage that when either the cartridge or the battery requires replacement, both must be removed and disassembled. Impregnated media devices and gel or paste devices also suffer the disadvantage that the quantity of air freshening material remaining therein is difficult to ascertain. This is especially true in the case of impregnated media devices where it is impossible to visually observe of the amount of material remaining in the media. With devices of these types, the material supply will often be depleted and the device will operate ineffectively for a period of time until the depletion is discovered and the supply renewed. Alternatively, the supply is often renewed prior to depletion, thereby resulting in material waste.
Liquid reservoir air freshener devices have been designed which overcome this disadvantage of the other two types of air freshener devices. These liquid reservoir devices often include a material supply container or bottle for automatically replenishing the material evaporated from the reservoir. The supply bottle is typically supported in an inverted position above the reservoir with the open mouth of the bottle in contact with the surface of the liquid in the reservoir. With such an arrangement, liquid material will flow out of the supply bottle only when the liquid level within the reservoir drops below the mouth of the bottle to break the suction and permit air to enter the bottle. An absorbent wick is often placed partially inside the reservoir to enhance the evaporative process.
In air freshener devices of this type, the supply bottle can be replaced when empty without interrupting the air freshening function of the device because a quantity of liquid material still remains within the reservoir for evaporation into the ambient. However, prior art devices of this type have no provision for ascertaining the level of liquid within the reservoir without dismantling at least a portion of the device itself. Hence, substantial effort is required to monitor the condition of the reservoir and supply bottle of these prior art devices. Often, the supply bottle may be emptied and the material completely evaporated from the reservoir before the depleted condition is discovered. In addition, complex supporting structures are often used in these prior art devices for supporting the supply bottle above the reservoir.
Prior art air freshener devices which function as liquid evaporators by employing motor-driven fans typically are not compact in construction. The deodorant material supply, battery and motor-driven fan are often mounted at spaced locations within a boxy or cumbersome housing, with little attention given to efficient packaging. These devices make use of a wick structure immersed in a reservoir containing a quantity of liquid material to be dispensed into the ambient. Substantially all of the vaporization of this material occurs from the surface of the wick itself, and the liquid supply is replenished only infrequently. These devices suffer the disadvantage that the amount of deodorizer that is vaporized gradually diminishes as the supply in the reservoir decreases. This results in an excessive release of fragrance at the start, and an insufficient release towards the end. This is due to the dilution of the concentration of the volatile fragrances as time passes, since the reservoir is always open, and the crusting over of the vaporization surfaces with the passage of time.
The prior art is, therefore, devoid of a wall-mounted air freshener device which is efficient, reliable, compact, attractive and unobtrusive.